Relieving attachment



April 3, 1928.

J. W. DURKEE RELIEVING ATTACHMENT Filed Jan. 10, 1925 A TTORNEY Patented Apr. 3, 1.928.

UNITED STATES PATENT OFFICE.

JAMES W.- DURKEE, OF HARTFORD, CONNECTICUT, AS SIGNOR TO FRATT WHITNEY COMPANY, OF NEW YORK, N. Y., A

CORPORATION OF NEW JERSEY.

' RELIEVING ATTACHMENT.

Application filed January This invention relates to lathes and in particular to a relieving attachment thereor. It is a primary object of the invention to provide an improved and smoother acting relieving mechanism applicable to the ordinary engine lathe and designed, in the illustrated embodiment-,for exterior relieving exclusively;

It is another object of the invention to provide a relieving attachmentcomprising a rotary cam adapted to move along the lathe bed together with the tool carriage and provided with a cam follower connected tofthe cross tool slide and operative to reciprocate the cross slide in timed relation to the rotation of the cani and the work.

It is another object'of the invention to im prove the form .of relieving attachment, and particularly the mounting for the cam, disclosed'in the patent to Lindstroni 1,516,196.

With the above and other objects in view, my invention consists in the features of construction and operation set forth in the following specification and illustrated in the accompanying drawings.

In the drawings annexed hereto and forming a part of this specification, I have shown but one embodiment of my invention applied to a tool makers engine lathe, but it will be understood that the invention can be otherwise embodied and that the: drawing is not to be construed as defining or liniiting the scope of the invention, the claims appended to this specification being relied upon for that purpose.

Referring to the figures 0 -Figure 1 is a plan view of relieving attachment.

Fig. 2 is an end elevation thereof partly in section.

Fig. 3 is a sectional View taken upon line 33 of Fig. 2.

f the drawings the complete Fig. 4 is a side elevation of a portion of the relieving mechanism.

Fig. 5 is an end elevation ofthe mechanism, and V Fig. 6 is a detail of the means for mounting the relieving attachment upon a taper attachment.

Briefly, and in its broadest aspect, my invention comprises a relieving attachment or mechanism mounted as shown in the patent to Lindstrom above mentioned and adapted primarily for exterior relieving opupon the sli 10, 1925. Serial No. 1,631.

erations, improved connections being interposed between the shaft for rotating the cam and fixed parts of the carriage so that the cam will have a smoother and more uniform action during relieving operations.

In the drawings, 1 indicates the bed of a lathe, '2 the tool carriage slidable along the base upon ways 3 thereon, {1' a taper attache ment on the carriage 2.- A tool slide 5 is mounted on the taper slide 4:, and a tool supporting slide 6 is adjustable upon the slide 5. is adapted to engage a nut 8 on the tool slide 5 whereby the latter may be adjusted de 4. A former or'taperbar 10 is mounted in a guide 11 on bracket12 secured to'the bed 1. The bar 10 is provided with a yokeshaped portion 13 on which is mounted and secured a housing 15. This housing 15 preferably is secured to the yoke 13 by means of a pin or pivot 14. The other or forward end of this housing 15 is slidably mounted on the taper slide 4;, as shown clearly in Fig. 3, and the housing 15 furthermore is'provided wit-h a pair of projecting ears 16 having slots 17 therein providing means for adjustably securing the housing 15 to the taper bar 10 in any angular adjusted position.

A rotary cam 19 is keyed or splined ona shaft 20 journaled in the housing 15, this shaft 20 being driven by gearing from the lathe headstock spindle in the usual-manner, Forconnections such as required for rotating this shaft, attention'is called :to copending application 609,030 in which a universal type of relieving attachment is de-. scribed and its driving means from the work spindle fully disclosed. A block 21 is mounted for reciprocation transversely of the shaft 20. This block is provided with asingle cam follower 22 positioned as shown 7 upon the block 21 at the rear side of the cam 19. Preferably this follower 22 is provided with a rotatable roller 23 to contact with the periphery of the cam 19. A bolt 2 1 extends vertically through the'block 21 and the taper slide 4 so that the slide 4 is moved directly with theblock 21. The bar 10 at this point is transversely recessed as shown A screw 7 journaled in the taper slide 4 at 25 to permit transverse movement of these It willbe seen from the above that rotation of the cam 19 will operate to draw the cross slide 5 and its tool toward and from the work transversely of the direction of movement ofcarriage 2. An adjustable stop 30 is providedthreadedinto the forward end of the housing 15 for limitingthe reciprocatory movement of the block 21,

thereby limiting the relieving movements of the tool.

The shaft 20-=for rotating. thecam 19 is shownmost'clearly in Fig. 3 and is provided with a connection shown in section in this: figure, permitting angular adjustment of the-shaft'20relative to its driving connection 38. F or this purpose there is'provideda two-part clutch, one member-having a tapered recess; This recess is engaged by the'iendofshaft 20 on which is suitably keyed or splined the relieving cam 19 above described. The members forming theconnection 32 are-held together by screws 34 so that the connection 33 positivelydrives the recessed member 32.

Surrounding the shaft 20 carryingthe cam 19 is a'sleeve-35 suitably splined to the shaft 20-and keyed to the sleeve 35 are plates 86 forming members of a friction clutch. The middle friction plate 37 ofthis clutch is at tachediby-means of' a screw to the housing 15 so that it cannot rotate. By means of a nut 38'engag ing the-threaded end of the cam shaftsleeve 35, pressure may be applied to the friction plates 36 and 37 of the clutch tovary the friction between them.

Nuts 39 on the threaded-end of the shaft 20 serve'to force the sleeve 35 axially against thecam 19 and to draw the conicalend of shaft 20 into 1 frictional engagement with the-recessedmember 32. Byloosening these nuts 39, the shaft '20 may he rotatedto any angulariposition relative to its driving con: nection'33.

-Ini operation, duringthe relieving action the cam follower23 rides over alternate recessed" and I raised portions of the cam 19 and; during the relieving: operations the chatteringcaused-thereby may be disagreeable." In" order to .obviate thiaja constant dragjor 'load is placed onthe cam 19 by means of the friction clutch formed by the plates 36 and 37 so that as the follower 23 rides over the higher points of the cam 19 there will be no tendency for the cam 19 to be forced ahead'and thus cause 'thefollower to drop suddenly upon a recessed portion. The cause of chatter or other disagreeable noises is thereby obviated and the action of the relieving mechanism is made smoother and more uniform.

l Jhat I claim is: p

1. A relieving attachment for lathes,-.com prising in combination, a carriage, a tool slide thereon, a rotary cam on said carriage,

a shaft for rotating the cam, a. cam follower on said slide, means normally holdinglhe follower in engagement with the cam,-.an.d a friction clutch comprisingitwomembers, one clutch member being attachedtothe carriage whereby it is held from rotation and the other attached to the cam rotating shaft and adapted to rotate therewith- 2. A relieving attachment for lathes com:- prising in combination, a carriage a tool slide thereon, a rotarycam on said carriage, ashaft for rotating the cam, a camifol-lower on the tool slide, means normally holding the follower in engagement withthe cam, a sleeve splined to the shaft, and a friction clutch comprisingtwo members, oneclutch member being fixedly attached to the car riage and the other attached to and adapted to rotate with the sleeve. l i

3. A relieving attachment forlathes come prising incombination, a carriage, aftool slide thereon, a rotarylcam on'said carriage, a shaft for rotating the cam, a camgfo'llower on the tool slide, meansnormally holding the follower in engagement, with -the cam, a sleeve splined to the. cam rotating shaft, a multiple disk friction clutchvdisposed be tween the carriage and th-esleeve, one of said disks being fixedly attachedto said car+v riage and another diskbeing attachedtoand adapted to rotate with saidsleeve, fl-Ildlllllk ual means to vary the friction between said disks.

In testimony whereof,'I hereto aifixr'my signature. V JAMESMW. DURKEE; 

